Military-specific automotive vehicles are often moved or transported from one location to another via a lifting system utilizing multiple elongate slings extending between a common lifting vertex and spaced apart connection points on the vehicle, e.g., for lifting vehicles by a crane to load and off-load vehicles from trucks, ships, railway cars, etc., or for more distant transport of a vehicle by a sling system suspended from a transport helicopter or other aircraft.
By contrast, however, most passenger and other commercially produced vehicles sold to the general public are not suitable for movement or transport via a sling lifting system. The frame components used in such vehicles are engineered in configurations designed to receive horizontally imposed forces as may occur in accidents with other horizontally moving vehicles, but otherwise the frame components in such commercially produced general purpose vehicles are typically relatively thin-walled and not suitable to withstand vertically applied forces on the order of forces as would occur during a sling lifting operation without deformation or damage to the vehicle frame.
Furthermore, as automotive safety technology applicable to passenger and other commercial vehicles has advanced in recent years, automotive engineers have learned that increased rigidity and strength of vehicle frame and body components does not necessarily promote or insure the safety of vehicle passengers and occupants, but to the contrary can be harmful to the extent that forces exerted on a vehicle in a crash or other accident can be transmitted unabated directly to occupants by a rigid vehicle structure. Accordingly, it has become commonplace for vehicle designs to include frame and body components designed to deform under forces generated in an accident, usually referred to as “crumple zones,” intended to absorb such forces and thereby mitigate the forces imposed on vehicle occupants. However, such deformation or crumple zones exacerbate the inability of commercial vehicle frames to withstand vertical lifting forces exerted by sling lifting systems when moving and transporting vehicles as the forces exerted in lifting vehicles can be transmitted through the slings to cause deformation to the frame or body components in the regions of the crumple zones.
The sling lifting of military vehicles via military aircraft presents even greater concerns in avoiding potential frame damage to the vehicles. Hence, military specifications, e.g., U.S. Department of Defense Specifications MIL-STD-209, MIL-STD 913, and MIL-STD 1366, specify standardized requirements for sling lifting of military vehicles. Military vehicles are typically manufactured with reinforced structural frames that do not include crumple or deformation zones, and therefore are less subject to potential damage under the loading forces imposed during sling lifting operations. Various commercially produced general purpose vehicles could offer advantages if adapted for military use, but would almost certainly suffer frame or body damage or deformation under such sling loading forces.
Accordingly, a need exists for an improved system for sling lifting of vehicles providing greater resistance to loading forces to prevent damage to vehicle frame components, e.g., crumple zones in vehicle frames. In turn, such an improved lifting system could greatly expand the possibilities for military adaptation of vehicles not originally built for military purposes.